Moisture dissipative floor covering layer

ABSTRACT

A carpet or carpet tile structure for mounting onto an underlying flooring surface comprising a backing layer having a top surface that is connected to a face fabric and a bottom surface that defines a plurality of fluid flow paths for dissipating moisture.

FIELD OF THE INVENTION

The present invention relates to flooring products. More particularly, the present invention pertains to a backing for a flooring material that permits moisture dissipation and air circulation between a bottom surface of the backing and an underlying flooring surface.

BACKGROUND OF THE INVENTION

A finished floor conventionally consists of a flooring surface supported by a sub-floor. The nature of the sub-floor depends upon the flooring surface it needs to support and the environment in which it functions. For example, for carpet flooring material in a home, the sub-floor may simply consist of construction grade plywood. If the sub-floor is in contact with the ground, such as for example in slab construction or in basement floors, moisture intrusion is possible.

Carpets, carpet tiles, and other flooring materials can be constructed with backings designed to prevent moisture penetration of spilled liquids through the backings and onto the underlying flooring surface. These same backings can prevent moisture that is retained between the backing and the underlying flooring surface from escaping.

Moisture retained between the carpet backing and the flooring surface can provide an environment that is ideally suited for undesirable microbial growth. Further, residual moisture retained between the backing and the flooring surface can cause physical damage to the floor surface, can prevent proper drying, can cause the flooring adhesive to release, or can result in microbial growth.

Residual moisture problems can occur in construction projects such as, for example, installing flooring materials on fresh or “green” concrete. During the curing process, moisture will be released from the concrete for an extended period of time. Moreover, it is common for moisture to communicate to the concrete surface from the underlying ground. Similarly, since many conventional flooring adhesives are water-based, they often emanate moisture during the curing process.

Accordingly, it is desirable to have a flooring material that can be applied to a flooring surface that allows moisture to dissipate and air to circulate between the bottom of the flooring material and the underlying flooring surface.

SUMMARY

The present invention pertains to underlayments and backing layers for flooring products. An illustrative aspect of the present invention is directed to a flooring material for mounting to an underlying flooring surface, such as, for example, a carpet or carpet tile structure. In this aspect, the carpet or carpet tile structure comprises a face fabric and a backing layer. In one aspect, a top surface of the backing layer is connected to at least a portion of a bottom side of the face fabric. A portion of a bottom surface of the backing layer defines a plurality of fluid flow paths such that at least one of the plurality of fluid flow paths extends to at least a portion of one side edge of the structure. The plurality of fluid flow paths allows the backing layer to dissipate moisture from between the bottom surface of the backing layer and the underlying flooring surface.

In one aspect, in use, at least one of the plurality of fluid flow paths that extend to the side edge of a first piece of structure are in fluid communication with at least one of the plurality of fluid flow paths that extend to the side edge of an adjoining, second piece of structure when the first and second pieces of structure are positioned onto the underlying flooring surface.

Additional aspects of the invention will be set forth, in part, in the detailed description and Figures which follow, and in part will become obvious from the detailed description, or may be learned by practice of the invention. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention as disclosed.

DETAILED DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate several aspects of the invention and together with the description, serve to explain the principles of the invention.

FIG. 1 is a partial cross-sectional schematic view of one aspect of the present invention showing a carpet or carpet tile structure having a backing layer, which is disposed on an underlying flooring surface.

FIG. 2 is a partial cross-sectional schematic view of one aspect of the present invention showing a carpet or carpet tile structure having a precoat layer and a backing layer, which is disposed on an underlying flooring surface.

FIG. 3 is a partial cross-sectional schematic view of one aspect of the present invention showing a carpet or carpet tile structure having a first adhesive layer and a backing layer, which is disposed on an underlying flooring surface.

FIG. 4 is a partial cross-sectional schematic view of one aspect of the present invention showing a carpet or carpet tile structure having a first adhesive layer, a reinforcing fabric layer, and a backing layer, which is disposed on an underlying flooring surface.

FIG. 5 is a partial cross-sectional schematic view of one aspect of the present invention showing a carpet or carpet tile structure having a first adhesive layer, a reinforcing fabric layer, a second adhesive layer, and a backing layer, which is disposed on an underlying flooring surface.

FIGS. 6-9 are a partial bottom plan views of aspects of the positioning of shaped spaced male protrusions on a backing layer of the present invention showing a row axis R of spaced male protrusions being offset rotationally at an acute angle α relative to a longitudinal axis L of the bottom surface of the backing layer.

FIG. 10 is a partial bottom perspective view of one aspect of the carpet or carpet tile structure of the present invention showing a plurality of spaced male protrusion distributed on and extending from the bottom surface of the backing layer.

FIG. 11 is a partial cross-sectional view of the carpet or carpet tile structure of the present invention taken across line 11-11 of FIG. 10, showing a plurality of troughs defined on the bottom surface of the backing layer.

FIG. 12 is an expanded view of a portion of FIG. 11 showing a female depression defined in the distal end of the male protrusion.

FIG. 13 is a partial bottom perspective view of one aspect of the carpet or carpet tile structure of the present invention showing a backing layer formed from a resilient spacer member.

FIG. 14 is a partial cross-sectional view of the carpet or carpet tile structure of the present invention taken across line 14-14 of FIG. 13.

FIG. 15 is a graphic plot of average drying rate of alternative aspects of the present invention with male protrusions on the backing layer in comparison to backing layers without male protrusions.

FIG. 16 is a graphic plot of inches dried per day of alternative aspects of the present invention with male protrusions on the backing layer in comparison to backing layers without male protrusions.

FIG. 17 is a schematic of an exemplary method of manufacturing a carpet or carpet tile structure of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

The present invention is more particularly described in the following exemplary aspects that are intended as illustrative only since numerous modifications and variations therein will be apparent to those skilled in the art. The exemplary aspects are now described with reference to the figures, in which like reference characters indicate like parts throughout the several views.

Before the present articles, compositions, devices, and/or methods are disclosed and described, it is to be understood that this invention is not limited to the specific articles, devices, and/or methods disclosed unless otherwise specified, as such may, of course, vary. It is also to be understood that the terminology used herein is for the purpose of describing particular aspects only and is not intended to be limiting.

Throughout this application, where patents are referenced, the disclosures of these patents, in their entireties, are hereby incorporated by reference into this disclosure.

As used herein, the singular forms “a,” “an” and “the” include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to “a fiber” includes aspects having two or more such fibers unless the context clearly indicates otherwise.

Ranges may be expressed herein as from “about” one particular value, and/or to “about” another particular value. When such a range is expressed, another aspect includes from the one particular value and/or to the other particular value. Similarly, when values are expressed as approximations, by use of the antecedent “about,” it will be understood that the particular value forms another aspect. It will be further understood that the endpoints of each of the ranges are significant both in relation to the other endpoint, and independently of the other endpoint.

The present invention is a backing system for a floor covering. The contemplated products for use of the present invention include, but are not limited to, carpets, carpet tiles, and the like. “Carpet” means a broadloom textile flooring product manufactured for and intended to be used in roll form. “Carpet tile” denotes a modular floor covering, usually in 18″×18,″ 24″×24″ or 36″×36″ squares, but other sizes and shapes are also within the scope of the present invention.

In accordance with the present invention, it should be noted that the carpet tile aspect of the present invention can comprise broadloom carpet that is cut into modular, i.e., tile pieces. However, it is contemplated that the carpet tile aspect can comprise broadloom carpet that does not comprise cut up broadloom carpet. In particular, and as one example, carpets normally retain dimensional stability by stretching and affixing the structure across the length and/or width of a room. The broadloom carpet product is generally affixed to retain the carpet in a stretched form by attaching the carpet to tacks, gluing the carpet to the floor or by some other method. In contrast, for carpet tiles, dimensional stability (which means that the carpet tile backing will not experience horizontal growth or shrinkage) is typically designed into the carpet tile structure itself because of its considerably smaller size and different intended uses. Also, a carpet tile must not experience cupping or curling (turning up or down of the edges) that would detract from the aesthetic and functional operation of the tile. Thus, a carpet tile is normally designed with reference to its end use as a carpet tile. Carpet tiles are normally prepared by preparing a 6 ft. width of material designed specifically for use as carpet tiles and cutting the width into the desired size for use.

The present invention pertains to a backing layer or underlayment for a flooring material such as, for example, carpet or carpet tiles. When applied to carpet and carpet tile, the backing layer of the present invention permits moisture dissipation and air circulation between the bottom surface of the backing layer and the underlying flooring surface. Such moisture drainage and air circulation is intended to improve the durability of the flooring product, improve the adhesion of the flooring material, as well as minimizing possible undesirable microbial growth and damage to the underlying flooring surface.

While, as noted, carpet and carpet tiles are separate aspects of the present invention, the basic structure of a face fabric of these aspects are not critical to the invention and, as such will be discussed together. Additionally, the underlayment itself can be used in other traditional flooring products such as, for example, hardwood flooring, laminate flooring, and the like.

In a first aspect of the invention, wherein the invention is a carpet or carpet tile structure for mounting onto an underlying flooring surface 500, a face fabric 100 is provided. The carpet or carpet tile structure has at least one side edge 110. The face fabric 100 can be, for example, either a tufted greige good, a fusion bonded material, or a woven and needle punched material. Such forms are well known to one of ordinary skill in the art. The face fabric 100 has a top side 120, i.e., the side that is exposed in use and a bottom side 130, i.e., the side that faces the floor 500 in use. The top side 120 is opposite the bottom side 130.

In whatever type of face fabric 100 that is used, the face yarns 140 comprise a plurality of fibers 150 that may be made from one or more of the following fiber types: polyolefins, polyamides, polyesters, polyethylene terephthalate (PET) and polytrimethylene terephthalate (PTT). The present invention is not limited to the selection of any specific type of fiber for a face yarn and, as such, may include other fibers, such as natural fibers.

To prepare an exemplary tufted griege good, a yarn formed from a plurality of fibers is tufted, woven or needle punched into a primary backing material 200 such that portion of the attached plurality of fibers 150 extend from the face side 210 of the primary backing material 200. In one example, a portion of the plurality of fibers 150 is exposed on the back side 220 of the primary backing material 200. The tufting, weaving or needle punching can be conducted in any manner known to be suitable to one of ordinary skill in the art which will not be discussed in detail herein. To fix the yarn 140 to the primary backing material 200, a precoat layer 300, such as, for example, an adhesive material, can be applied to at least a portion of the back side 220 of the primary backing material 200. In one aspect, a portion of the precoat layer 300 substantially penetrates therein at least a portion of the primary backing material 200. In another aspect, the portion of the precoat layer 300 serves to substantially consolidate at least a portion of the fibers 150 that are disposed therein the primary backing material 200. Further, the precoat layer 300 can be substantially moisture impervious.

An adhesive material can be used to form the precoat layer 300. Such material can be one of a number of materials known in the art to be suitable for such use. As non-limiting examples, the precoat material can comprise one or more of: styrene-butadiene rubber (SBR), polyvinyl chloride (PVC), ethylene vinyl acetate (EVA), polyesters, polyurethanes, polyolefins, emulsified polymers, butadiene methamethacrylic acid (BDMMA) and vinyl acetate ethylene (VAE). Still further, the precoat material may comprise homogenously branched ethylene polymer (HBEP) as disclosed in U.S. patent application Ser. No. 09/032,893 (the '893 application), the disclosure of which is incorporated herein in its entirety by this reference.

In the present invention, a woven or a non-woven primary backing material 200 can be used. The type of primary backing material desired will depend on various factors including, but not limited to, whether carpet or carpet tile is being made, the desired end-use for the product (e.g., commercial or residential), the type of face yarn 140 used and the price of the product. One example of a suitable woven primary backing material is 28×18 woven primary, style no. 1002764 from Synthetic Industries, Calhoun, Ga. One example of a suitable non-woven primary backing material is Colbond UMT 135, manufactured by Colbond, Enka, N.C. Other types of primary backing materials 200 are also suitable for use herein such as, for example, hydraentangled fibers and fiberglass.

A fusion bonded face fabric 100 is characterized by a plurality of cut pile yarns, for example, nylon or other natural or synthetic fibrous-type material, implanted in an adhesive layer, particularly a thermoplastic, like a polyvinyl chloride layer or a hot-melt adhesive layer. Where a polyvinyl chloride plastisol layer is used, heating of the layer gels and then fuses the layer into solid form, while with hot-melt adhesive material; a melted layer is applied and subsequently cooled into solid form. The plurality of fibrous yarns is bonded to and extend upright from the adhesive base layer to form a face wear surface. Methods of making fusion bonded face goods are known and described, for example, in U.S. Pat. No. 6,089,007, the disclosure of which is incorporated in its entirety by this reference.

Regardless of the face fabric 100, one aspect of the invention the carpet or carpet tile structure 10 also has a backing layer 400. In this aspect, the backing layer 400 has a top surface 410, an opposed bottom surface 420, and at least one side edge 430. In use, the top surface 410 of the backing layer 400 is proximate to the bottom side 130 of the face fabric 100 and the opposed bottom surface 420 is proximate to a floor or subfloor. The top surface 410 of the backing layer 400 is connected to at least a portion of the bottom side 130 of the face fabric 100. Where a precoat layer 300 is applied to at least a portion of the back side of the primary backing material 200, the top surface 410 of the backing layer 400 underlies at least a portion of the precoat layer 300.

In one aspect, a portion of the bottom surface 420 of the backing layer 400 defines a plurality of fluid flow paths 440. At least one of the plurality of fluid flow paths 440 extends to at least a portion of one side edge 430 of the structure. These fluid flow paths 440 of the backing layer 400 dissipate moisture from between the bottom surface 420 of the backing layer 400 and the underlying flooring surface 500.

In another aspect, at least one of the flow paths 440 that extends to the side edge 430 of a first piece of structure is in fluid communication with at least one of the flow paths 440 that extends to the side edge 430 of an adjoining, second piece of structure when the first and second pieces of structure are positioned onto the underlying surface 500. This way, moisture can be dissipated to adjoining carpet or carpet tile structures.

The backing material used to form the backing layer 400 can be one of a number of materials known in the art to be suitable for such use. As non-limiting examples, the backing material can comprise one or more of: a thermoset material or a thermoplastic material. Still further, the backing material may comprise any of the exemplary materials as disclosed in U.S. Patent Application No. 2002/0134486, the disclosure of which is incorporated herein in its entirety by this reference. Yet further, the backing layer can comprise any material that is suitable for forming the backing structure herein and such material include materials that can be embossed or molded. Exemplary materials include HBEP, polyethylene, polypropylene, polyurethane, PVC, and the like. An antimicrobial material can be included in the backing material, if desired.

In one aspect, at least a portion of the bottom surface 420 of the backing layer 400 has a plurality of spaced male protrusions 450 extending therefrom. In this aspect, the spaces between the male protrusions form the aforementioned fluid flow paths 440. In one aspect of the present invention, each spaced male protrusion 450 has a distal end 452 with a cross-sectional shape. In one example, the cross-sectional shapes of all of the spaced male protrusions 450 are uniform. In another example, the spaced male protrusions 450 have at least two different cross-sectional shapes at the distal end 452.

In use, the spaced male protrusions 450 define a plurality of contact points between the flooring material and floor or sub-floor 500. As discussed in more detail below an adhesive can be used to durably attach the flooring material to the flooring service. Adhesive can also fill in a portion of the plurality of fluid flow paths 400 to adhere an inner portion of the plurality of fluid flow paths 44 to the flooring surface 500.

In one aspect, the spaced male protrusions 450 are distributed about the bottom surface 420 of the backing layer 400. It is contemplated that the spaced male protrusions 450 can be distributed about the entire bottom surface 420 or they can be distributed about only select portions of the bottom surface 420.

One example of the invention comprises spaced male protrusions 450 having a substantially circular cross-sectional shape at the distal end 452. However, as one skilled in the art will note, it is contemplated that many varied cross-sectional shapes can be used, such as, for example, star shapes, hexagonal shapes, pentagonal shapes, crescent shapes, square shapes, rectangular shapes, and like shapes. One will appreciate that these exemplary shapes are not intended to be limiting.

In another aspect, the distal end 452 of each spaced male protrusion has a cross-sectional area. In one example, the cross-sectional areas of the distal ends of all of the spaced male protrusions are approximately equal. In another example, the spaced male protrusions have at least two different cross-sectional areas. In a further aspect, the distal end of at least one of the plurality of male protrusions defines a female depression 454 that provides the distal end 452 of the male protrusion 450 more surface area to contact the flooring adhesive.

As one will appreciate, the bottom surface 420 of the backing layer 400 can have a longitudinal axis L. In one example, the plurality of spaced male protrusions is arranged in a random pattern. In another example, the plurality of spaced male protrusions is arranged to form a plurality of spaced parallel rows of substantially co-axial spaced male protrusions. Each row of the spaced male protrusions can extend along a row axis R. In one aspect, the spaced male protrusions 450 in adjacent parallel rows are staggered in relation to each other. In another aspect, the row axis R is offset rotationally at an acute angle α relative to the longitudinal axis L of the bottom surface 420 of the backing layer 400. In one example, the acute angle α is between about 50 to about 500. More particularly, the acute angle α is between about 100 to about 400.

In one aspect of the invention, the bottom surface 420 of the backing layer 400 defines a plurality of troughs 480. Each trough has a minimum depth “d” and a minimum width “w”. In one aspect, the minimum depth of each trough 480 is approximately equal. In yet another aspect, as one will appreciate, it is contemplated that the minimum depth of each trough 480 can vary across the bottom surface 420. In one example, the minimum depth of each trough can be between about 0.010 inches to about 0.100 inches. More particularly, the minimum depth of each trough can be between about 0.020 inches to about 0.080 inches. Still more particularly, the minimum trough depth can be at least about 0.030 inches.

In another aspect, the minimum width “w” of each trough 480 is approximately equal. In an alternative aspect, as one will appreciate, it is contemplated that the minimum width of each trough 480 can vary selectively across the bottom surface 420 of the backing layer 400. In one example, the minimum width of each trough can be between about 0.020 inches to about 0.120 inches. More particularly, the minimum width of each trough can be between about 0.040 inches to about 0.100 inches. Still more particularly, the minimum trough width can be about 0.060 inches.

In yet another aspect, as one will appreciate, the troughs 480 form the aforementioned fluid path ways 440. As described above, in one aspect, at least one trough of a first piece of structure is in fluid communication with at least one trough of an adjoining, second piece of structure when the first and second pieces of structure are positioned onto the underlying flooring surface 500.

In an alternative aspect, the backing layer 400 comprises a resilient spacer member 490. The resilient spacer member 490 defines multiple fluid flow paths that provide for moisture dissipation and air circulation between the bottom of the resilient spacer member 490 and the underlying flooring surface 500. In one aspect, the spacer member 490 comprises a matrix 492 of substantially self-supporting, randomly convoluted polymeric filaments 494. In one example, the matrix 492 has a cross-sectional thickness of between about ⅛ inch and about ¾ inch. In another example, the polymeric filaments 494 have a diameter of between about 0.010 inch and about 0.040 inch. In yet another example, the spacer member contains an antimicrobial material. The spacer member 490 can also be substantially moisture impervious.

The matrix 492, in accordance with the above, can be substantially self-supporting, and provides multiple relatively open flow paths therethrough. It is characterized by having a composite strength in compression without collapsing. This spacer member 490 is preferably provided as roll stock, to facilitate its application to an overlying surface portion of a raw tufted carpet roll. In one aspect, the spacer member 490 is provided in a roll of approximately 36 inches in width and 33 or 66 feet in length. In another aspect, the matrix 492 of the spacer member 490 is smooth or substantially smooth on one side to enable the spacer member to abut fairly uniformly onto the underlying surface of the overlying surface.

In one aspect, the matrix defined by the spacer member 490 thus comprises a matting of randomly convoluted filaments 494 or wires, joined at points at which they abut, to provide in the aggregate a resilient characteristic. In one example, desired properties may be achieved through the use of nylon filaments. It is contemplated that the matrix can include an antimicrobial material.

Nylon, as is well known, is a thermoplastic polyamide resin, the filaments of which may be heat fused to one another at randomly spaced points. The randomly convoluted and mutually interconnected filaments 494 are advantageously formed by extrusion of molten polymer through articulated spinnerets. U.S. Pat. Nos. 3,687,759, 3,691,004 and 4,212,692 teach methods and apparatus for forming matrices of the kinds employed in the spacer member of the present invention, the disclosure of which are incorporated in their entirety by this reference.

In one aspect of the invention, an adhesive layer 600 is disposed between at least a portion of the bottom side 130 of the face fabric 100 and the top surface 410 of the backing layer 400. As one will appreciate, an adhesive composition can be used form this adhesive layer 600 which affixes the face fabric 100 to a backing layer 400. Such an exemplary adhesive composition can comprise at least one laminating adhesive. In accordance with the present invention, a number of materials can be used as the laminating adhesive. In some aspects, the laminating adhesive can comprise one or more of a polyolefin such as HBEP, LLDPE (linear low density polyethyelene), ULDPE (ultra low density polyethylene), HDPE (high density polyethylene), MDPE (medium density polyethylene), low density polyethylene (LDPE), polypropylene, PVC, hot melt adhesives, (SBR), BDMMA or VAE. Still further, the laminating adhesive can comprise HBEP. Yet still further, the laminating adhesive can comprise any adhesive material that is capable of adhering the face fabric material, such as the exemplified primary backing material, to the backing layer.

Yet still further, the laminating adhesive can comprise a polyolefin material (as defined above) and a second polymer material. The second polymer material can comprise one or more of: HBEP, ULDPE, LDPE, LLDPE, ULDPE, MDPE, HDPE, grafted polyethylene (e.g. a maleic anhydride extrusion grafted heterogeneously branched linear low polyethylene or a maleic anhydride extrusion grafted homogeneously branched ultra low density polyethylene), ethylene acrylic acid copolymer, ethylene vinyl acetate copolymer, ethylene ethyl acrylate copolymer, polystyrene, polypropylene, polyester, polyurethane, polybutylene, polyamide, polycarbonate, rubbers, ethylene propylene polymers, ethylene styrene polymers, styrene block copolymers, vulcanates, SBR, hot melt adhesive, BDMMA or VAE. Still further, the second polymer material can be any material that is suitable for blending with the laminating adhesive so as to enhance or moderate the resulting delamination strength. Exemplary adhesive compositions are known and described, for example, in U.S. patent application Ser. No. 10/879,884, the disclosure of which is incorporated in its entirety by this reference.

Irrespective of the type of laminating adhesive, the adhesive composition can contain flame retardants, colorants, tackifiers, or other materials that would be useful to, for example, improve processability, aesthetic properties, etc.

In an alternative aspect, a reinforcing fabric layer 700 can be disposed between the first adhesive layer 600 and the top surface 410 of the backing layer 400. Dimensional stability, i.e., the ability of the tile to maintain its size and flatness over time, can be a desirable property in a carpet or carpet tile. The inclusion of reinforcing fabric layer 700 can enhance the dimensional stability of carpet or carpet tile made according to this aspect. Exemplary suitable reinforcing materials include dimensionally and thermally stable fabrics such as non-woven or wet-laid fiberglass scrims, as well as woven and non-woven thermoplastic fabrics (e.g. polypropylene, nylon and polyester). In one example, the reinforcing fabric layer is a polypropylene non-woven fabric sold by DuPont™ as “Xavan®” with a basis weight of 3.5 oz/yd². Alternatively, reinforcing fabric layer 700 is a fiberglass scrim sold by ELK Corp. as “Ultra-Mat” with a basis weight of 1.4 oz/yd².

In one aspect, the face fabric 100 can have an second adhesive layer 650 connected to and underlying at least a portion of the face fabric 100, such as, for example, the laminating adhesive discussed herein above. In this aspect, the second adhesive layer 650 is disposed between the reinforcing fabric layer 700 and the top surface 410 of the backing layer 400. For example, the adhesive can be connected to and underlie at least a portion of the reinforcing fabric layer 700 and the backing layer 400, such as, for example, the resilient spacer member 490, can be adhered to and underlie at least a portion of the second adhesive layer 650.

In another aspect, the present invention provides a floor covering underlayment 800 that has at least one side edge 810 and can be positioned between a flooring surface and a overlying conventional flooring material (not shown), such as, for example, carpet, carpet tiles, laminate and the like. Such a floor covering underlayment 800 has a bottom surface that has a plurality of spaced male protrusions 450 that extend downwardly from the bottom surface. In one aspect, the spaced male protrusions 450 are distributed about the bottom surface of the underlayment 800. It is contemplated that the spaced male protrusions can be distributed about the entire bottom surface or they can be distributed about only select portions of the bottom surface. Further, it is contemplated that the spaced male protrusions 450 are constructed and arranged about the bottom surface of the underlayment is the manner described above. Additionally, the bottom surface of the underlayment can define a plurality of troughs 480 therebetween the spaced male protrusions, forming at least one fluid flow path 440. At least one of the fluid flow paths extends to at least one side edge of the underlayment such that moisture can dissipate from between the bottom surface and the underlying flooring surface 500. One would appreciate that the floor covering underlayment 800 is the backing layer 400 described above without an attached face fabric.

One exemplary method of manufacturing a carpet or carpet tile structure according to this invention comprises: 1) providing a face fabric 100 that has a bottom side 130, as well as yarn 140 attached thereto; 2) applying a backing layer 400 onto at least a portion of the bottom side 130 of the face fabric 100; and 3) forming a bottom surface 420 of the backing layer to create a plurality of fluid flow paths 440 thereon. At least one of the plurality of fluid flow paths 440 extends to at least one side edge 110 of the structure such that the backing layer dissipates moisture from between the bottom surface 420 of the backing layer 400 and the underlying flooring surface 500.

In another aspect, an adhesive material, such as a precoat layer 300 can be disposed on at least a portion of the back side 200 of the primary backing material 200 such that a portion of the precoat layer substantially penetrates therein at least a portion of the primary backing material. Further, the precoat layer 300 can consolidate at least a portion of the yarn disposed therein the primary backing material 200. In this example, the backing layer 400 is applied to the precoat layer 300. The precoat material can be applied to the carpet in various conventional ways. For example, the precoat material can be applied directly, such as with a roll over roller applicator, or a doctor blade. Alternatively, the precoat material can be applied indirectly, such as with a pan applicator. After the application of the precoat material, heat can be applied to the back side of the primary backing material 200 so as to dry the dispersion and, alternatively, to at least partially melt the material to fix the plurality of fibers, i.e., yarn, to the primary backing material.

In one aspect of the invention, the backing material can be extruded onto the bottom side 130 of the face fabric 100, either with or without adhesive precoat. In this aspect, the face fabric 100 passes between a nip roller 900 and a chilled embossed roller 910 with the bottom side 130 of the face fabric 100 facing away from the nip roller 900 and toward the chilled embossed roller 910.

In one aspect of a method of manufacturing a carpet or carpet tile structure, the step of forming the bottom surface 420 comprises forming a plurality of spaced male protrusions 450, such as the ones described above. In one example, an extruder 920 is mounted so as to extrude a molten polymeric material suitable to prepare the backing material. The polymeric material is extruded through the die and onto the face fabric at an upstream location before the nip roller 900 and the chilled embossed roller 910. Methods of extruding a polymeric material are disclosed in detail in U.S. patent application Ser. No. 09/032,893, the disclosure of which is incorporated herein in its entirety by this reference. In one example, the backing material contacts the face fabric before passing between the nip roller and the chilled embossed roller. The chilled embossed roller can be embossed with depressions that are positioned, sized and shaped to form the spaced male protrusions in the bottom side of the backing layer.

In one aspect, as depicted in FIG. 17, the face fabric 100 with the polymeric material applied thereto passes from the nip roller 900 and the chilled embossed roller 910 to a cooling drum 930 with the backing layer facing the cooling drum. The size of the cooling drum 930 and the length of time the carpet rolls against it can be varied depending on the level of cooling desired in the process. The cooling drum 930 can be cooled by passing ambient or chilled water through it. After passing over the cooling drum 930, the face fabric/backing layer combination is brought over a turn roller 940. At this point, the carpet can be rolled up and stored for future sale or use.

As one can appreciate, the backing layer 400 can be formed separately from the face fabric. The backing layer can be extruded and embossed as described above. It can also be molded or formed in any other conventional manner. The backing layer can then be used as a separate underlayment or it can be adhered to the face fabric of a carpet or carpet tile structure, for example, using the laminating adhesive discussed further hereon.

In accordance with the present invention, it has surprisingly been found that superior adhesion of a flooring material to a flooring is seen. That is, the plurality of fluid flow paths have been found by the inventors herein to provide improved adhesion of a flooring material to a flooring surface when attached to a floor using adhesive. In particular, unlike with prior art flooring materials in which adhesives do not dry completely after installation, the backing materials of the present invention provide markedly improved drying profiles. Without being bound by theory, it is believed that the plurality of fluid flow paths allow the adhesive to dry more completely in comparison to the adhesion of backings not having these plurality fluid flow paths.

The following examples are put forth so as to provide those of ordinary skill in the art with a complete disclosure and description of how the present invention is practiced, and associated processes and methods are constructed, used, and evaluated, and are intended to be purely exemplary of the invention and are not intended to limit the scope of what the inventors regard as their invention. Efforts have been made to ensure accuracy with respect to numbers, but some errors and deviations should be accounted for.

Illustrated examples of the drying behaviors of backings having the pluralities of fluid flow paths are shown in FIGS. 15 and 16. The primary performance criteria determined for the various examples was drying time of moisture between the backing layer and the simulated flooring surface.

At this time, it is believed that the flooring materials of the present invention are suitable for use with conventional adhesive materials generally used for adhering carpet and carpet tiles to flooring materials. Non-limiting examples of such adhesives include solvent-based adhesives, water based adhesives and emulsions. As further examples, acrylic adhesives are suitable for use in the invention.

In order to set up the test, sample carpet structures were cut into four (4) 2′×3′ rectangles. Two of the rectangles were prepared using a flat HBEP backing system and two were prepared using an HBEP backing system having a plurality of spaced male protrusions so as to provide the plurality of fluid flow paths as described above. For this test, the protrusions were cylindrical in shape, having a ¼″ diameter, a 0.03″ height, and are spaced 0.06″ apart. The protrusions in the backing system were embossed into the HBEP backing layer using an embossing roller.

A 4′×8′ piece of transparent ⅜″ Plexiglas® was supplied to simulate a flooring surface. On half of the Plexiglas sheet a pressure sensitive adhesive, specifically Shaw N-5000 (an acrylic, water-based, pressure sensitive adhesive), was applied with a standard 3/16″ v-notch trowel. On the other half of the Plexiglas sheet the same pressure sensitive adhesive was applied with a ⅜″ nap paint roller.

Into the wet adhesive applied with the v-notch trowel, one rectangle of carpet with the conventional backing system was installed and one rectangle of carpet with the backing system containing the plurality of spaced male protrusions was installed. The two remaining rectangles were installed into the wet adhesive applied with the paint roller.

The sheet of Plexiglas was then laid flat on the floor and rolled with a 100 lb roller. At that point, visible moisture was measured at eight points on each sample and the distance of the moisture from the edge of the sample was recorded. The data were measured and recorded every 24 hours.

In both FIG. 15 and FIG. 16, line A represents the data corresponding to the carpet structure containing the backing layer with the plurality of spaced male protrusion installed using adhesive which was applied with the paint roller. Line B represents the data corresponding to the carpet structure containing the backing layer with the plurality of spaced male protrusions installed using adhesive which was applied with the v-notch trowel. Similarly, Lines C and D represent data corresponding to the carpet structure containing the backing layer without the spaced male protrusions installed with an adhesive which was applied with a paint roller and a v-notch trowel, respectively.

FIG. 16 depicts the results of this test in terms of the number of inches of backing dried per day. FIG. 15 shows the results of this test in terms of average drying rate, shown in inches per day. As can be seen in FIGS. 15 and 16, both of the samples prepared with an exemplary backing of this invention dried at much faster rates than the samples with the conventional backing. In fact, as can be seen in FIG. 16, the samples with the conventional backing observed no appreciable drying at all, while the samples with the exemplary backing of this invention both had significant measurable drying observed.

Observations indicate that the drying profile of the backing material herein provide more effective drying in use, especially when used on 6 foot carpet structures.

Although several aspects of the invention have been disclosed in the foregoing specification, it is understood by those skilled in the art that many modifications and other aspects of the invention will come to mind to which the invention pertains, having the benefit of the teaching presented in the foregoing description and associated drawings. It is thus understood that the invention is not limited to the specific aspects disclosed hereinabove, and that many modifications and other aspects are intended to be included within the scope of the appended claims. Moreover, although specific terms are employed herein, as well as in the claims which follow, they are used only in a generic and descriptive sense, and not for the purposes of limiting the described invention, nor the claims which follow. 

1. A carpet or carpet tile structure, the structure having at least one side edge, comprising: a face fabric having a bottom side; and a backing layer having a top surface and an opposed bottom surface, wherein the top surface of the backing layer is proximate to at least a portion of the bottom side of the face fabric, wherein at least a portion of the bottom surface of the backing layer defines a plurality of fluid flow paths, and wherein at least one of the plurality of fluid flow paths extends to at least a portion of one side edge of the structure such that, when the structure is applied to an underlying flooring surface, the fluid flow paths of the backing layer dissipate moisture from between the bottom surface of the backing layer and the underlying flooring surface.
 2. The carpet or carpet tile structure of claim 1, further comprising a first adhesive layer disposed between the at least a portion of the bottom side of the face fabric and the top surface of the backing layer.
 3. The carpet or carpet tile structure of claim 1, wherein the at least one of the plurality of fluid flow paths that extend to the side edge of a first piece of the structure are in fluid communication with the at least one of the plurality of fluid flow paths that extend to the side edge of an adjoining, second piece of the structure when the first and second pieces are positioned onto the underlying flooring surface.
 4. The carpet or carpet tile structure of claim 1, wherein the face fabric comprises: a primary backing material having a face side and a back side; a plurality of fibers attached to the primary backing material and extending from the face side of the primary backing material, a portion of the plurality of fibers being exposed on the back side of the primary backing material; and a precoat layer disposed on at least a portion of the back side of the primary backing material, wherein a portion of the precoat layer substantially penetrates therein at least a portion of the primary backing material and substantially consolidates at least a portion of the fibers disposed therein the primary backing material, wherein the top surface of the backing layer underlies at least a portion of the precoat layer.
 5. The carpet or carpet tile structure of claim 1, wherein a portion of the bottom surface of the backing layer has a plurality of spaced male protrusion extending therefrom, whereby the plurality of fluid flow paths are defined therebetween the plurality of spaced male protrusions.
 6. The carpet or carpet tile structure of claim 5, wherein the plurality of spaced male protrusions comprise a plurality of spaced parallel rows of substantially co-axial spaced male protrusions, wherein each row extends along a row axis.
 7. The carpet or carpet tile structure of claim 6, wherein the male protrusions in adjacent parallel rows are staggered in relation to each other.
 8. The carpet or carpet tile structure of claim 7, wherein the bottom surface of the backing layer has a longitudinal axis, and wherein the row axis is offset rotationally relative to the longitudinal axis of the bottom surface at an acute angle α.
 9. The carpet or carpet tile structure of claim 8, wherein the acute angle α is between about 10° to about 40°.
 10. The carpet or carpet tile structure of claim 5, wherein each spaced male protrusion has a distal end having a cross-sectional shape.
 11. The carpet or carpet tile structure of claim 10, wherein the cross-sectional shapes of all of the spaced male protrusions are substantially uniform.
 12. The carpet or carpet tile structure of claim 10, wherein the spaced male protrusions have at least two different cross-sectional shapes at the distal end.
 13. The carpet or carpet tile structure of claim 10, wherein the cross-sectional shape is substantially circular.
 14. The carpet or carpet tile structure of claim 5, wherein each spaced male protrusion has a distal end having a cross-sectional area.
 15. The carpet or carpet tile structure of claim 14, wherein the cross-sectional areas of the distal ends of all of the spaced male protrusions are substantially the same.
 16. The carpet or carpet tile structure of claims 14, wherein the spaced male protrusions have at least two different cross-sectional areas.
 17. The carpet or carpet tile structure of claim 5, wherein the bottom surface defines a plurality of troughs, each trough having a minimum depth and a minimum width, and wherein each trough forms a portion of one fluid flow path.
 18. The carpet or carpet tile structure of claim 17, wherein at least one trough of a first piece of structure is in fluid communication with at least one trough of an adjoining, second piece of structure when the first and second pieces of structure are positioned onto the underlying flooring surface.
 19. The carpet or carpet tile structure of claim 5, wherein the plurality of spaced male protrusions are distributed about the bottom surface.
 20. The carpet or carpet tile structure of claim 19, wherein the plurality of spaced male protrusions are arranged in a random pattern.
 21. The carpet or carpet tile structure of claim 5, wherein a distal end of at least one of the plurality of male protrusions defines a female depression.
 22. The carpet or carpet tile structure of claim 21, wherein the distal end of substantially all of the plurality of male protrusions defines a female depression.
 23. The carpet or carpet tile structure of claim 1, wherein the backing layer comprises a resilient spacer member, wherein the spacer member spaces the bottom side from the underlying flooring surface to dissipate moisture from beneath the bottom side, the plurality of fluid flow paths being defined therethrough the spacer member.
 24. The carpet or carpet tile structure of claim 23, wherein the spacer member comprises a matrix of self-supporting, randomly convoluted polymeric filaments, the matrix having a thickness of from about ⅛ inches to about ¾ inch.
 25. The carpet or carpet tile of claim 24, wherein the polymeric filaments have a diameter of from about 0.010 inches to about 0.040 inches.
 26. The carpet or carpet tile structure of claim 1, wherein the backing layer comprises a polyethylene or PVC.
 27. The carpet or carpet tile structure of claim 1, wherein the backing layer is formed from a thermoplastic material or a thermoset material.
 28. The carpet or carpet tile structure of claim 1, wherein the backing layer is substantially moisture impervious.
 29. The carpet or carpet tile structure of claim 2, further comprising a reinforcing fabric layer disposed between the first adhesive layer and the top surface of the backing layer.
 30. The carpet or carpet tile structure of claim 29, further comprising a second adhesive layer disposed between the reinforcing fabric layer and the top surface of the backing layer.
 31. A backing layer for a floor covering, such as a carpet or a carpet tile, having at least one side edge, comprising: a side edge; and a bottom surface, wherein at least a portion of the bottom surface defines a plurality of fluid flow paths thereon, and wherein at least one of the plurality of fluid flow paths extends to at least a portion of the side edge of the backing layer such that the backing layer dissipates moisture from between the bottom surface of the backing layer and an underlying flooring surface when the backing layer is applied to the underlying flooring surface.
 32. The backing layer of claim 31, wherein at least a portion of the bottom surface has a plurality of spaced male protrusions extending therefrom, whereby the plurality of fluid flow paths are defined therebetween the plurality of spaced male protrusions.
 33. The backing layer of claim 32, wherein the bottom surface further defines a plurality of troughs therebetween the spaced male protrusions, and wherein each trough forms a portion of one fluid flow path.
 34. The backing layer of claim 32, wherein the bottom surface of the backing layer has a longitudinal axis, wherein the plurality of spaced male protrusions comprises a plurality of spaced parallel rows of substantially co-axial spaced male protrusions, each row extending along a row axis, wherein the male protrusions in adjacent parallel rows are staggered in relation to each other, and wherein the row axis is offset rotationally at an acute angle α relative to the longitudinal axis of the bottom surface.
 35. A method of manufacturing a carpet or carpet tile structure for mounting onto an underlying flooring surface, the structure having at least one side edge, comprising: providing a face fabric having a bottom side, wherein the face fabric comprises yarn attached thereto; applying a backing layer onto at least a portion of the bottom side of the face fabric; and forming a bottom surface of the backing layer to create a plurality of fluid flow paths thereon at least a portion of the bottom surface, wherein at least one of the plurality of fluid flow paths extends to at least one side edge of the structure such that the backing layer dissipates moisture from between the bottom surface of the backing layer and the underlying flooring surface.
 36. The method of claim 35, wherein the step of forming the bottom surface comprises forming a plurality of spaced male protrusions, each male protrusion having a distal end and extending outwardly away from the bottom surface of the backing layer, whereby the plurality of fluid flow paths are defined therebetween the plurality of spaced male protrusions.
 37. The method of claim 36, wherein the bottom surface further defines a plurality of troughs, and wherein each trough forms a portion of a fluid flow path of the plurality of fluid flow paths.
 38. The method of claim 36, wherein the plurality of spaced male protrusions comprise a plurality of spaced parallel rows of substantially co-axial spaced male protrusions, each row extending along a row axis, wherein the bottom surface of the backing layer has a longitudinal axis, and wherein the row axis is offset rotationally relative to the longitudinal axis of the bottom surface at an acute angle α.
 39. The method of claim 38, wherein the male protrusions in adjacent parallel rows are staggered in relation to each other.
 40. The method of claim 35, further comprising, prior to the step of applying the backing layer, applying an adhesive layer to at least a portion of the bottom side of the face fabric, wherein the backing layer is applied to the adhesive layer.
 41. The method of claim 40, wherein the backing layer comprises a resilient spacer member, wherein the spacer member spaces the bottom side from the underlying flooring surface to dissipate moisture from beneath the bottom side, the plurality of fluid flow paths being defined therethrough the spacer member.
 42. The method of claim 35, further comprising, prior to the step of applying the backing layer, applying a first adhesive layer onto at least a portion of the bottom side of the face fabric, applying a reinforcing fabric layer onto at least a portion of the first adhesive layer, and applying a second adhesive layer onto at least a portion of the reinforcing fabric layer, wherein the backing layer is applied onto at least a portion of the second adhesive layer.
 43. The method of claim 35, wherein the step of forming the bottom surface of the backing layer occurs before the step of applying the backing layer onto at least a portion of the bottom side of the face fabric.
 44. A floor covering underlayment having at least one side edge, comprising: a bottom surface having an longitudinal axis, a portion of the bottom surface of the floor covering underlayment having a plurality of spaced male protrusions extending therefrom, the bottom surface further defining a plurality of troughs therebetween the spaced male protrusions, wherein each trough forms a fluid flow path, and wherein at least one of the formed fluid flow paths extends to the at least side edge of the underlayment such that moisture can dissipate from between the bottom surface and an underlying flooring surface.
 45. The floor covering underlayment of claim 44, wherein the bottom surface has a longitudinal axis, wherein the plurality of spaced male protrusions comprises a plurality of spaced parallel rows of substantially co-axial spaced male protrusions, each row extending along a row axis, wherein the male protrusions in adjacent parallel rows are staggered in relation to each other, and wherein the row axis is offset rotationally in relation to the longitudinal axis of the bottom surface at an acute angle α.
 46. The floor covering underlayment of claim 45, wherein at least one of the plurality of troughs of a first piece of underlayment are in fluid communication with at least one of the plurality of troughs of an adjoining, second piece of underlayment when the first and second pieces of underlayment are adjoined on the underlying flooring surface.
 47. A carpet or carpet tile structure, the structure having at least one side edge comprising: a face fabric having a bottom side; and a backing layer having a top surface and an opposed bottom surface, wherein in the top surface of the backing layer is proximate to at least a portion of the bottom side of the face fabric, wherein at least a portion of the bottom surface of the backing layer defines a plurality of fluid flow paths that are suitable for allowing moisture dissipation when the structure is applied to an underlying flooring surface. 